Upgrade to Ray 2.43

[comaniac]

• Ray 2.41+ has API changes.
• Ray 2.42 has a bug that breaks PP in v0

Accordingly, we will wait until Ray 2.43, and upgrade the Ray version in vLLM as well as the APIs.

[ruisearch42]

Ray 2.43 should be released in a couple of days. Will bump soon.